Download - E2-E3 Electrical Technical

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E2-E3

Electrical Technical

Automation & Remote Monitoring/

Controlling of EMS- An Overview


WELCOME

• This is a presentation for the E2-E3 Electrical (Technical)

Module for the Topic: Automation & Remote

Monitoring/Controlling of EMS – An Overview .

• Eligibility: Those who have got the Up gradation to from

E2 to E3.

• This presentation is last updated on 15-3-2011.

• You can also visit the Digital library of BSNL to see this

topic.


AGENDA

What is Automation?

Advantages of Automation

Monitoring and Controlling a process/operation

from Remote Location?

Benefits of Monitoring and Controlling of EMS

from a Remote Location


• Automation is the application of information

Technology(IT) and control systems to control

industrial machinery and processes, replacing human

operators.

• Automation of the processes can be done with either

Microcontroller or PLC (Programmable Logical

Controller).

Automation


• Automation examples:

• An ATM (Automated Teller Machine)

• Automated Telephone Switchboards

Automation


Microcontroller

• A microcontroller is a small computer on a

single integrated circuit consisting of a relatively simple

CPU combined with support functions.

• In addition to all arithmetic and logic elements (ALU) of

a general purpose microprocessor, the microcontroller

usually also integrates additional elements such as

read-only and read-write memory, and input/output

interfaces.


Microcontroller/PLC based automation(An Illustration)


• PLC Consists of input module, CPU & Output

module.

• Input accept variety of digital & analog signals from

various field devices & converts it into logical signals

that can be used by CPU.

• CPU makes decisions and execute control

instructions based on program instruction in memory.

Programmable Logic Controller(PLC)


Operator

Interface

Programming

Device

Output

Module

CPUInput

Module

CPUInput

ModuleOutput

Module

CPUInput

ModuleOutput

Module

CPUInput

ModuleOutput

Module

CPUInput

Module



• Output module converts control instruction from CPU

into digital or analog signal that can be used to control

various field devices (actuators).

• A programming device is used to input desired

instructions. These instruction determine what the PLC

will do for a specific input.

• An operator interface device allow process

information to be displayed and new control

parameters to be entered (Configuration).



Programmable Logic Controller(PLC) based Automation – A very simple example


• A microcontroller-based design would be appropriate

where hundreds or thousands of units will be

produced and so the development cost (design of

power supplies and input/output hardware) can be

spread over many sales

• And where the end-user would not need to alter

the control.

Microcontroller Vs PLC


• PLCs are suitable for severe conditions (dust, moisture,

heat, cold, etc) and have the facility for extensive

input/output (I/O) arrangements. These connect the PLC to

sensors and actuators.

• PLC applications are typically highly customized systems

so the cost of a packaged PLC is low compared to the cost

of a specific custom-built micro-controller design.

• Automation with PLC is also suitable when the changes to

the system would be expected during its operational life.

Microcontroller Vs PLC


Major Components of Automation System:

• PLC/ Micro controller

• Sensor

• Actuator

Components of Automation


Components of Automation(Contd..)

• PLC/ Micro controller

• Is a processor, also known as heart of any

automation system, which does the arithmetic and

logical processing and takes decision accordingly.

It also contains memory to retain the data & control

unit to control various functional units etc.

• It monitors inputs and make decision based on

instruction held in the program memory.




• Sensor

• Is a device that connect a physical condition into

an electrical signal for use by the PLC.

• Sensors are connected to input of a PLC.

• Example : An electrical signal is sent from push

button to PLC indicating the condition of the push

button contacts.




• Actuator

• Convert a electrical signal from PLC into physical

condition.

• Connected to PLC output.

• Example: Motor starter.



Advantage of PLC / Microcontroller

• Wiring between devices & relay contacts is done in

PLC program.

• Hardwiring is required only to connect field

devices (less intensive).

• Easier to create & change program in PLC than

to wire or rewire.

• Smaller physical size than hardwire solutions.

• Application can be documented.


Examples of PLC

• Siemens make :

S7-200 micro PLC; small size; power supply &

I/O are on board; for smaller & standalone

application.

S7-300 & S7-400 for more complex

application; greater nos. of I/O points; power

supply & I/O separate modules.


Simple Automation System–At a Glance


I/Os to an Automation system

Inputs/outputs to an Automation system could be

• Digital

• Analog

• Digital ON/OFF; digital input; pushbuttons; toggle

switches etc.

• Analog Continuous & Variable signal; 0-20 mA or

0-10 V; Example -Level transmitter.


PLC Scan Cycle

• PLC program is executed as as part of a

repetitive process referred to as a scan.

• (1) Read Input

(2) Execute program

(3) Internal diagnostic & Communication

tasks

(4) Update output.


Remote Monitoring & Controlling

• Ability to monitor a process from a remote location &

controlling the process from the remote location.

• We Can have central data base in control room to log

the process details and to store the appropriate

commands (like changing parameters) for controlling the

process based on conditions received.

• Communication between local and remote unit can be

achieved by – cable modem or wireless.

• Various critical parameters can be altered and controlled

from a remote end.


Benefits of Remote Monitoring

• Several critical parameters can be monitored at different

scattered locations.

• Labour, Time & Money saving in monitoring & controlling.

• More Efficient Monitoring at an overall less cost.

• Retain data at central server which can be helpful at times

of debugging an erroneous condition.

• On demand dispatch of Engineers.
